WHITEFLY: New pest invades Beach trees and plants

September 27, 2012

A new insect from Central America is affecting native vegetation by sucking the sap out of the leaves of plants and trees on Estero Island and other island communities.

The rugose spiraling whitefly may not be directly killing palm trees, gumbo limbos and other plant life during their feeding process, but these unwelcomed pests are weakening the tree's immune system and might be opening up the door for other pathogens or weather conditions to do the job.

"It's much like a mosquito, except it's on a plant," said Stephen H. Brown, Lee County Extension Director & Horticulture Program Leader.

Article Photos

Whiteflies are leaving a white mark on the leaves of coconut palms and gumbo limbo trees on at Red Coconut RV Park.

BOB PETCHERThis gumbo limbo tree at Mound House shows the affects of the whitefly.

Brown calls the rugose spiraling version of the whitefly a "recent pest" that is doing more harm than another species of the whitefly that arrived in 2009 and caused "defoliation and branch dieback of ficus" in Florida.

"Essentially, it seems like it is making its biggest impacts on the barrier islands," he said. He listed Sanibel Island, Pine Island, Bonita Beach and Fort Myers Beach among the whitefly targets. "It is a big problem."

Red Coconut RV Park co-owner Fran Myers said she found out that the whitefly had made its way onto her property when a Truly Nolen Pest Control representative was making a regular service call on Sept. 21. Her park has more than 200 palm trees and other plants and trees as well.

"He said that if we have (the whitefly problem), the whole island probably has it," said Myers. "If you bend over the stack of one of the palm fronds, it looks like somebody sprinkled baking powder on them."

The white "housing unit" for the whitefly is apparent on the backside of leaves or fronds. According to a report done by Brown, you cannot miss their inhabitance.

"The undersides of the leaves are covered with an abundance of white, waxy material and the top with excessive black sooty mold. The sooty mold is a particular nuisance, as it also accumulates on uninfected understory plants, mulch, gravel, concrete, automobiles and even on the surface of water. The preamble to the sooty mold is a sticky material known as honeydew, a sugary substance that is food or the sooty mold fungus," the report read.

Many pest control companies are controlling with a "root trench" procedure, where the chemical is mixed and poured at the base of the plants. Granules are also being used, but these measures need to be applied frequently.

Systematic insecticides as opposed to contact insecticides are needed to control the pests. They are absorbed by the plant's roots and trunk and move upward to the area of feeding.

"The goal there is that the plants will pick it up and make the leaves toxic to the bugs. The problem is only 25 percent of the chemical actually gets into the tree, so there is a lot of waste and a lot of chemical going into the environment," said A Better Bugman Owner Jim Lambeth.

Lambeth believes injecting the tree is a better solution. His company uses Arborjet, a tree injection system, that states the procedure lasts for 12 to 14 months.

"Our company injects the tree and 100 percent of the active ingredient is eaten by the tree," he said. "The most common chemical used for these bugs is called imidacloprid. It has a really quick knock down. In reality, we are guaranteeing it for six months, then inspect at that point to determine if we are really going to get that kind of residual."

Lambeth disclosed Sanibel is completely infested with whiteflies. So far, on the Beach, his company has treated GullWing, Best Western Plus and Tropical Sands and has proposals out on at least a half dozen other large properties.

He says that since so many plants and trees will never get treated, they will remain infested.

"We are going to treat the trees that people actually pay us to treat, but the whiteflies will move into trees that have not been treated," said Lambeth. "Hopefully, the residuals will hold up. This will be a long-term fight."

Ant populations have increased at the base of infected trees due to the honeydew left by the whiteflies. Once the trees are treated, the ant armies will need to go elsewhere, probably inside homes and businesses.

"Whereas it doesn't kill the plant directly, the economical impact stands to be fairly significant across the board," said Lambeth. His company has begun sending flyers to area chambers of commerce to inform them about the whitefly.

"Even with our injection system, it is not a quick fix," he stressed.

Whiteflies have been known to feed on a variety of plants, like the gumbo limbo, black olive and Brazil beautyleaf trees as well as palms, such as areca and coconut and foxtail and bird of paradise shrubs. It does not discriminate against native, exotic, or invasive plants, the report said. The big gumbo limbo tree on the Mound House property has been affected as well.

Brown said that since this species of whitefly is relatively new to the area, it has few natural enemies, which makes it even more dangerous.

"Once local predatory insects and mites soon realize that a new dish has been added to the menu, they will act accordingly," he wrote.

Red Coconut RV Park maintenance worker Jeanne Price was on site when Truly Nolen noticed the whitefly problem and has seen the infestation grown in just a few days time. She remembers the whitefly species of 2009, and she knows this one is a little more problematic.

"The last whitefly that came here only defoliated our ficus trees. It didn't kill them because it didn't affect the roots. Apparently, this one goes to the roots," she said. "With all this rain we've been having, we should have beautiful leaves on these trees and plants."